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From: "d.thibaud at systemique dot fr" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug math/17211] New: tan function is very slow compared to tanf function
Date: Tue, 29 Jul 2014 09:36:00 -0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=17211

            Bug ID: 17211
           Summary: tan function is very slow compared to tanf function
           Product: glibc
           Version: 2.18
            Status: NEW
          Severity: normal
          Priority: P2
         Component: math
          Assignee: unassigned at sourceware dot org
          Reporter: d.thibaud at systemique dot fr

Created attachment 7729
  --> https://sourceware.org/bugzilla/attachment.cgi?id=7729&action=edit
source code used to verify tan slowdown

Why tan function from 2.18 (fedora 20) is very slow compared to same function
in 2.12 (cents 6.5) or tanf from 2.18 ?

code provided with tanf function runs in 125ms. Same code with tan function
takes 3.2s.
This is a huge slowdown in code using tan instead of tanf.

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